https://bugs.freedesktop.org/show_bug.cgi?id=89980
--- Comment #10 from falaca@gmail.com --- I wanted to add that I built Mesa 10.1 from git and installed it on Ubuntu 15.04. Along with Xorg 1.17.1 and the latest DDX compiled from git, I can't observe the bug.
Is there anything else that I can do to help this along? I tried cloning the master branch and just reverting Marek's commit (the one that I narrowed the bug down to with my git bisect), but of course that didn't work since there is other newer code which now depends on that.
I also tried disabling hyperz (since I believe 10.2 turned hyperz on by default), and that had no effect.